you might be able to get out of it. unplug PSU cable, jump the CMOS jumper and take the battery out. then let it sit. while that is sitting, get yourself to a machine and prepare a boot floppy. you can prepare a boot floppy with dr. dos:
http://www.phoenix.com/korea/support/download/dr-dos/
put the correct bios revision for your mobo on to this floppy. also, put the awdflash.exe from the asus site on to this floppy (latest is 8.23Z i believe for the a7n8x brand of boards). edit autoexec.bat on your floppy, and put this in there:
@echo off
AWDFLASH.EXE BIOS.bin /sn /py
replace BIOS with your bios filename
save it.
then go back to the machine. hook up a floppy, and you can disconnect the IDE drives if u like (not necessary though). if you would like to see Award's Boot Block, you can hook up a PCI video card, otherwise you will attempt a "blind" flash. take out the AGP card if you hook up the PCI video card. put the battery back in, and put CMOS jumper back to default. boot up with the floppy in the drive, when it powers up if you have a PCI video card, you should see Award Boot Block, and the floppy light should light up. You should now see it attempting to flash from the floppy. If you dont have a PCI video card, then you should just listen to the floppy and make sure it is reading from the floppy. If all was well, your machine should reboot after a few mins, and your machine will POST normally, and you can enter BIOS.
If bootblock doesnt kick in right away, turn off the machine, unplug, wait, then plug back in, and power up. If after a few attempts bootblock still hasnt kicked in, then I'm afraid that your BIOS chip is completely corrupted. You will have to get yourself another BIOS chip or you can hotflash the chip in another Nforce2 board.
good luck.